The study of the development of an organism during the embryonic and fetal stages of life.
Embryologies
D000818
Animals
Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.
Animal,Metazoa,Animalia
D012617
Sea Urchins
Somewhat flattened, globular echinoderms, having thin, brittle shells of calcareous plates. They are useful models for studying FERTILIZATION and EMBRYO DEVELOPMENT.
A genus of SEA URCHINS in the family Arbaciidae. They have only one spheridium (stalked body) per ambulacral area (contains tube feet); most sea urchins have several spheridia per area.